Multiple scanners, such as those in the dental industry, are based on laser triangulation. In these systems, a laser beam is projected on an object to be digitized, such as a dental casting, for example. By imaging the diffuse reflectance of the laser beam on the object, the distance to the object is measured and a three-dimensional (3D) image of the object can be reconstructed.
Numerous dental scanners include a single sensor to take images of a dental casting in order to create the 3D image. The sensor is displaceable in order to take images of different views of the dental casting. Then the dental scanner creates a 3D image of the dental casting from the different views and using data processing. The sensor is usually moved by means of a motor and the exact position of the sensor must be known when the images of the dental casting are taken. Because the movements of a motor are not always perfectly reproducible, an error on the sensor position can be introduced which affects the quality of the scan and periodic calibration of the scanner is needed to reduce the error on the sensor position.
Therefore, there is a need for an improved scanner.